JPS61235561A - Magnetron sputtering device - Google Patents

Abstract

PURPOSE:To form a thin film having good quality without film defects on a substrate by attaching and detaching successively a magnet contained in a target support to and from a target to control variably the intensity of the magnetic field to the target. CONSTITUTION:The inside of a vacuum vessel 1 is evacuated to a prescribed degree of vacuum and after a prescribed gas for reactive sputtering is introduced therein, the magnets 4a, 4b are brought near to the target 3 by a moving mechanism 41. A substrate support 7 is then rotated by a rotating mechanism 8 and a shutter 9 is opened. A prescribed high voltage is impressed to the substrate and target from a power source 10. The generated plasma-like sputter gaseous ions are focused by the magnetic field to sputter the target 3. The target 3 is then covered by the shutter 9 and the magnets 4a, 4b are detached from the target 3 by the moving mechanism 41. The sputtering is executed in the state of not focusing the sputter gaseous ions. The thin film having the good quality without the film defects such as abnormal projections and pinholes is formed on the substrate 6 by repeating properly and alternately the above- mentioned operation.

Description

[Detailed Description of the Invention] (FFI Required) In a magnetron sputtering apparatus that forms a thin film on a substrate by the reactive magnetron Yubaft method, a target disposed facing the substrate is provided with a target built in the target support. The magnets are installed so that they can be brought close to or separated from each other, and the magnetic field strength toward the target is variably controlled. A thin film is formed with the magnet brought close to the target, and then a thin film is formed with the magnet pulled away from the target. repeating the step of sputtering the target surface alternately to scatter and remove unnecessary reactants deposited on the surface of the non-sputtered region of the target during thin film formation, thereby preventing the deposited particles from adhering to the substrate surface; The purpose is to obtain a thin film without film defects.

[Industrial application field]

The present invention relates to the improvement of magnetron sputtering equipment used in the manufacture of various semiconductor integrated circuits and magnetic recording media, and in particular, when forming a thin film on a substrate by reactive magnetron sputtering, sputtering does not adhere to the non-sputtered portion of the target surface. The present invention relates to a structure of a target support that prevents reaction deposits from scattering and adhering to a substrate and causing film defects.

A magnetron sputtering device consists of electrodes on the substrate side on which a thin film is to be formed, which are placed facing each other in a reactive gas atmosphere consisting of an inert gas such as argon (Ar) gas and oxygen (0°) gas, and a magnet on the back side. A high voltage is applied between the flat targets provided, the generated plasma-like sputtering gas ions are focused by the magnetic field of the magnet, and the target is sputtered by Ar particles excited by the high-density plasma. A thin film is formed on a substrate at a high deposition rate.

As described above, the deposition rate of magnetron sputtering equipment is comparable to that of conventionally used various evaporation equipment and general sputtering equipment. It is widely used as a thin film forming apparatus for manufacturing recording media.

However, when a thin film is formed on a substrate by the reactive sputtering method using the above-mentioned apparatus, sputtering is performed in the strong magnetic field region of the target surface by the magnet, and sputtering is not performed in other regions, and conversely, the reactive sputtering material is There is a problem in that the deposits are peeled off and scattered and attached to the substrate as foreign matter, which causes defects in the produced thin film, and it is desired to solve this problem.

[Conventional technology]

FIG. 3 is a cross-sectional view of the main parts of a conventional magnetron sputtering device, in which a vacuum chamber l equipped with an exhaust device 2 is
A target support 5 in which a target 3 is supported and has a built-in annular magnet 4a and a central cylindrical magnet 4b which are magnetically coupled by a yoke 4c, and a substrate 6 on which a thin film is to be formed are arranged opposite to the target support 5. A supported substrate support 7 is arranged to be rotatable by a rotation mechanism 8. 9
is the shutter.

In order to form a thin film on the surface of the substrate 6 supported on the substrate support 7 using such an apparatus, the substrate support is A predetermined voltage is applied between the target 7 and the target 3 by a high voltage power source IO, and the shutter 9 is moved from above the target 3 to open it.

At this time, the plasma-like sputtering gas ions generated are
Target 3 by said magnet 4a + 4b
Sputtering gas ions focused by a magnetic field generated in an arc shape on the surface and excited by high-density plasma collide with the target 3, whereby sputtering material is sputtered from the surface of the target 3, and a large sputtering material is sputtered onto the substrate 6. A thin film is formed at a deposition rate.

[Problem that the invention seeks to solve]

By the way, in such a magnetron sputtering apparatus, the annular magnet 4a and the central cylindrical magnet 1
As shown in FIG. Since the sputtering occurs when the sputtering occurs, the area 21 is eroded, and the area other than the erosion area 21 becomes a non-functional area 22 where almost no sputtering occurs.

However, when a thin film is deposited on the substrate 6 by the reactive sputtering method using the sputtering apparatus as described above, most of the sputtered target material is deposited on the substrate 6, but some of the reactive sputter particles are There is a phenomenon in which reactants are deposited by colliding with gas ions in the plasma and adhering to the non-functional region 22 of the target 3.

In this case, the above-mentioned deposits not only have unstable adhesion but also generally have high resistance, so they gradually become electrically charged, and furthermore, they cause abnormal discharge, etc., and peel off, becoming coarse particles 31. The particles scatter and adhere to the generated film 32 of the substrate 6 as shown in FIG. 5, forming protruding defects on the film surface.

In addition, the coarse particles 31 have drawbacks such as weak adhesion to the produced film 32 (and easy peeling during various steps after the sputtering step, resulting in pinhole defects).

The present invention was made in view of the above-mentioned problems.
The purpose of this is that when sputtering is performed without applying a magnetic field to the target 3, sputtering gas ions in the plasma impinge on the entire surface of the target 3 at tE and sputtering is performed on the non-functional area of the target 3. Since the reaction deposits deposited on the target surface are scattered and removed, a simple magnet movement mechanism is used to variably control the application state and non-application state of the magnetic field distribution on the target surface.
It is an object of the present invention to provide a novel magnetron sputtering apparatus that enables the formation of a thin film without film defects by performing sputtering by repeating this state alternately.

Means for Solving Problem C] In order to achieve the above object, the present invention, as shown in FIG. The magnets 4a and 4b built into the target support 5 are brought close to each other by the moving mechanism 41,
Alternatively, the magnetic field strength of the target 3 can be variably controlled by providing it in a removable manner.

[Effect]

In such an apparatus configuration, the magnets 4a and 4b built in the target support 5 are brought close to the target 3 by the moving mechanism 41 to form a magnetic field distribution on the surface of the target 3, and then reactive sputtering is performed. A thin film is deposited on the opposing substrate 6.

Next, after covering the target 3 with a shutter 9, the magnets 4a and 4b are moved around the target 3 by a moving mechanism 41 so that no magnetic field distribution is formed on the surface of the target 3.
After that, sputtering is performed to remove the non-functional area 2 of the target 3 during the thin film formation.
The reaction deposits deposited on 2 are scattered and removed. By repeating such operations alternately, it becomes possible to obtain a thin film without film defects as in the conventional method.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a sectional view of a main part of an embodiment of a magnetron sputtering apparatus according to the present invention.

In the figure, reference numeral 1 denotes a vacuum container equipped with an exhaust device 2. In the vacuum container 1, a substrate support 7 supporting a substrate 6 on which a thin film is to be formed is rotatably arranged by a rotation mechanism 8. The target 3 is supported opposite to the annular magnet 4a, which is magnetically coupled by a yoke 4c, and a cylindrical magnet is placed at the center of the annular magnet t-4a.
A target support 5 having a built-in target 4b is arranged.

Further, the magnets 4a and 4b built into the target support 5 are installed so as to be able to approach or separate from the target 3 by a moving mechanism 41, and are configured to variably control the magnetic field strength with respect to the target 3.

Now, in order to form a thin film by reactive sputtering on the surface of the substrate 6 supported on the substrate support 7 using such an apparatus, first, the inside of the vacuum chamber 1 is heated to summer air dust of about 10-6 torr. After exhausting the vacuum chamber 1 using the exhaust device 2, a reactive sputtering gas containing argon (Ar) gas and oxygen (02) gas mixed at a predetermined volume ratio is introduced into the vacuum chamber 1.

In this state, the magnet) 4 is applied to the target 3.
a and 4b are brought closer to each other by a moving mechanism 41 as shown (not limited to this example), and the substrate support 7 supporting the substrate 6 is rotated by the rotating mechanism 8.
Furthermore, the shutter 9 between the substrate 6 and the target 3 is opened, and a predetermined high voltage is applied by the power supply 10.

At this time, the plasma-like sputtering gas ions generated are
The sputtering gas ions, which are focused by the magnetic field generated in an arc shape on the surface of the target 3 by the magnet 4 and excited by the high-density plasma, collide with the target 3 and are sputtered onto the substrate 6 in a large size. A thin film is formed at the film deposition rate.

After that, as shown in FIG. 2, after covering the target 3 with a shutter 9, the magnets 4a and 4b built in the target support 5 are moved by a mechanism that moves the magnets 4a and 4b built into the target support 5 so that no magnetic field distribution is formed on the surface of the target 3. 41, the sputtering gas is separated from the target 3 by a predetermined distance, and sputtering is performed without focusing the sputtering gas ions generated in the form of plasma.

In this way, sputtering can be performed on the entire surface of the target 3, and the non-functional area 22 of the target 3 can be sputtered during the thin film formation.
The reaction deposits deposited on the shutter 9 are scattered and removed toward the shutter 9 side.

By appropriately repeating these process operations alternately to form a thin film of a predetermined thickness on the substrate 6, it becomes possible to obtain a high-quality thin film without film defects such as foreign matter protrusions or pinholes. (Effects of the Invention) As is clear from the above description, according to the magnetron sputtering apparatus according to the present invention, the reaction deposits deposited on the non-functional area of the target surface are not scattered against the produced film on the substrate. This eliminates the problem of film adhesion and makes it possible to obtain a thin film of good quality without film defects such as foreign matter protrusions or pinholes as in the past.

Therefore, it can be applied to the manufacture of magnetic recording media, semiconductor integrated circuit elements, etc. with excellent effects.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a main part showing an embodiment of a magnetron sputtering apparatus according to the present invention, FIG. 2 is an enlarged cross-sectional view of a main part showing an embodiment of a magnetron sputtering apparatus according to the present invention, and FIG. 3 is a conventional FIG. 4 is a perspective view of a target surface phenomenon in a conventional magnetron sputtering device; FIG. 5 is a thin film formed by a conventional magnetron sputtering device. FIG. In Figures 1 and 2, 1 is a vacuum vessel, 3 is a target, 4a is an annular magnet, 4b is a central cylindrical magnet, 4c is a yoke, 5 is a target support, 6 is a substrate, and 7 is a substrate support. , 41 indicate moving mechanisms, respectively. Book 1 Mikanahi should happen [εtt view 7 Shikoku p Hanayu interrupts No. 211a Ju moat pattern required exts” to 1] year Haiha “i ■ revision ll 311 Conventional n7-γ゛I Hosinori I Taka-1 Power Figure No. 45! I】Ran 1yo I）Shinari'nlegffivMTsN&ff
iFigure 5

Claims (1)

[Claims] In a vacuum container (1), there is a target support (5) that supports a target (3) and has built-in magnets (4a) and (4b), and a substrate (on which a thin film is to be formed) facing the target support (5). A substrate support (7) supporting 6) is arranged, and a target (3) substance is deposited on the substrate (6) by sputtering while a sputtering gas atmosphere is created in the vacuum container (1). In the device configuration, the above target (
3) A magnetron sputtering apparatus characterized in that magnets (4a) and (4b) are provided so as to be able to approach or separate from the target (3), thereby variably controlling the magnetic field strength with respect to the target (3).